The instant invention relates to chart paper of the type used in chart recorders and the like and more particularly to a package for facilitating the loading and handling of chart paper of the type commonly referred to as Z-fold paper, i.e., paper which is folded in a zigzag configuration.
Many of the chart recording devices currently in use utilize Z-fold chart paper comprising an elongated strip of paper which has been folded in zigzag configuration to form a stack of paper wherein sequential fold lines of the paper define opposite first and second ends of the stack. In use, a stack of paper is received in a compartment in a recorder and one end of the paper is received in an advancing mechanism in the recorder, whereby the paper is gradually unfolded as it is dispensed from the stack and sequentially advanced to a stylus as needed. Z-fold paper of this type has been used in recorders to provide effective trouble free supplies of continuous paper therefor, and hence the use of Z-fold paper for chart recorders has become extensive.
While Z-fold chart paper of the above described type can be effectively used in chart recorders, it has been found that frequently stacks of Z-fold paper become inadvertently unfolded during the installation thereof in the proper compartments in recorders. In this regard, the inadvertent unfolding of a stack of Z-fold paper can represent a substantial inconvenience to an operator of the recorder who is attempting to effect the loading thereof because the paper must be manually refolded to the proper configuration before the attempted loading of the paper in the recorder can again be effected. Accordingly, heretofore the possiblity of the inadvertent unfolding of a stack of Z-fold paper during the attempted loading thereof in a recorder has represented a significant drawback to the use of such paper.
The instant invention provides a novel solution to the problems heretofore encountered in the loading of Z-fold paper into recorders by providing a Z-fold paper package which can be installed in a recorder without any risk of the paper being inadvertently unfolded. Specifically, the loading package of the instant invention comprises an elongated flexible wrapper of normally closed loop configuration which is snugly receivable on a stack of paper so that it extends along the upper and lower faces and ends thereof but which is separable to an open configuration to provide access to the paper subsequent to the loading of the package in a recorder. In the preferred embodiment of the package, the wrapper has first and second end portions which are detachably interconnected to define the separable closed wrapper loop. Further, the first and second end portions preferably terminate adjacent one end of the stack of folded paper and on the upper face thereof, and the first end portion terminates in a free tab portion so that the first end portions is separable from the second end portion upon movement of the tab portion towards the adjacent end of the stack. In addition, the Z-fold paper is preferably arranged so that the leading edge thereof is disposed adjacent the point where the first and second end portions of the wrapper are detachably interconnected. Accordingly, the loading package is receivable in the chart paper compartment of a recorder so that the interconnected end portions of the wrapper are adjacent the access opening of the compartment and thereafter the interconnected end portions can be separated by manipulation of the tab portion. The leading edge of the chart paper can then be fed into the advancing mechanism of the recorder and the paper may be dispensed from the stack as needed with the wrapper remaining in the paper compartment still surrounding the Z-folded paper. In the event that circumstances make it necessary to remove the unused portion of the paper stack from the paper compartment, the wrapper facilitates such removal without allowing the Z-folded paper to become inadvertently unfolded.
Devices representing the closest prior art to the instant invention of which the applicant is aware are disclosed in the U.S. patents to Weilby, U.S. Pat. No. 2,956,674, Lindenmuth et al., U.S. Pat. No. 3,443,093, Gendron et al., U.S. Pat. No. 3,631,972, and Smolderen, U.S. Pat. No. 4,093,069. While these patents disclose various devices for the packaging of sheet materials they do not disclose or suggest a package comprising a flexible wrapper of the type hereinabove set forth which can be utilized to facilitate the loading of Z-fold paper in a chart recorder. Hence, the above references are believed to be of nothing more than general interest.
It is, therefore, a primary object of the instant invention to provide a package which can be utilized to facilitate the loading of Z-fold chart paper in the chart paper compartment of a recorder.
Another object of the instant invention is to provide means to minimize the risk of having Z-fold paper become inadvertently unfolded during the loading thereof in a chart recorder.
Another object of the instant invention is to provde a flexible wrapper for Z-folded chart paper which can be inserted with the paper into the chart paper compartment of a recorder.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.